builtin-checkout.c: Remove unused prefix arguments in switch_branches path
builtin-checkout.c: Remove unused prefix arguments in switch_branches path

This path doesn't actually care where in the tree you started out,
since it must change the whole thing anyway. With the gratuitous bug
removed, the argument is unused.

Signed-off-by: Daniel Barkalow <29008086f408d0a471729b0d8667fa72ead76296@iabervon.org>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git